Week 02 - Computer-aided design

weekly schedule

Time block	Wed	Thu	Fri	Mon	Tue
Global class	3 h
Local class		1.5 h		1.5 h
Research	1 h	1 h	2 h	2 h
Design		1 h	4 h	2 h	5 h
Fabrication
Documentation	5 h	1 h	2 h	1 h	3 h
Review	1 h

overview

Week 2 focuses on exploring 2D and 3D design tools to model a possible final project. The goal is to evaluate different software options, document the modelling process, and learn proper image and video compression for web documentation.

learning objectives

Evaluate and select 2D and 3D software.
Demonstrate and describe processes used in modelling with 2D and 3D software.
Demonstrate image and video compression.

assignments

model experimental objects/part of a possible final project in 2D and/or 3D software.
show how I do it with words/images/screenshots.
document how I compress my image and video files.
include my original design files.

research

2D design - raster.

gimp According to their website, GIMP is a cross-platform image editor available for GNU/Linux, macOS, Windows and more operating systems. It is free software, you can change its source code and distribute your changes. GIMP provides you with sophisticated tools to get your job done. You can further enhance your productivity with GIMP thanks to many customization options and 3rd party plugins.

I followed the basic tutorials in their website for resizing dimensions, changing the file size and so on.

workflow description — Resizing detail 1/3.

Then I decide to do something more creative, but still easy, so I looked for a creative tutorial in Youtube. This is the one that I chose. So for my collage I took some random pictures from Pinterest and this is my process.

affinity

Time to try another rasterizing software, also free. In this case it will be affinity Pixel.

[!Creative freedom from Canva.] Affinity comes with built-in Vector, Pixel, and Layout studios, but you’re not locked in. Rearrange panels and mix and match your favourite tools to build custom studios. You can save multiple setups, switch between them in a click, and even share with others or download theirs. It’s customization that flexes to your workflow.

From this free image:

I converted into a vector image with the “Image trace” option.

Image Trace dialog: Edge Threshold set to 50% (controls which edges generate paths) and Curve Fitting Tolerance at 75% (higher values produce smoother, less precise curves). Clicking Apply converts the raster layer into editable vector paths.

Then, I went for a little more interesting task inspired by this tutorial , creating a mockup for a T-shirt. From this:

To this:

2D design - vector.

Adobe Illustrator. Adobe Illustrator is a great vector graphics editor and design software developed and marketed by Adobe.

In a past life used to play around with Illustrator so I went straight and recreate one of the León’s Fablab logos:

Recreation process in Adobe Illustrator: (1) Ellipse Tool (L) to draw the outer ring, (2) Rectangle Tool (M) to subtract the inner area and create the circular frame, (3) Type Tool (T) with Ubuntu Regular at 60 pt for the text. Final step: Type → Create Outlines to embed the font.

affinity affinity also offers a quite interesting substitute to Adobe Illustrator. Both programs share the similar shortcuts and ways to get the desired results. In this case I sketched a standing desk exploded-view.

Standing desk exploded view in Affinity Designer — Exploded-view sketch of the standing desk in Affinity Designer (Vector studio): (1) Rectangle Tool (M) to draw tabletop and leg components separately, (2) fill colors applied — brown for the tabletop, dark grey for the legs, (3) Type Tool (T) with Helvetica Regular 42 pt for the label. The two assembled views at the bottom show front and side elevation.

3D design.

Fusion 360.

Autodesk claims that Fusion is the right tool to transform your anyone’s product development process with integrated design, manufacturing, electronics, and data management in a single solution.

Short before starting the Fab Academy I started a Fusion for makers course. It doesn’t mean I have much experience, but I don’t start from zero.

This is the basic figure I have done so far:

3D Animation

So far I have feeling quite comfortable with Fusion 360, so I am going to try this part of the assignment with the same software.

The goal is to create a simple animation showing a standing desk going up and down, with telescopic legs (two-stage, three concentric square tubes per leg). One thing that I realized or found out is that Fusion 360 animates components, not bodies. My current model consists of multiple bodies inside a single component, so every piece that needs to move independently must be its own component. In order to understand the difference between bodies and components in Fusion 360, I checked this video.

Let’s create the sliding legs and the correspondent animation!

Fusion 360 project's component hierarchy.

Building the telescopic leg.

Each leg has three concentric square tubes:

Tube	Section	Height	Purpose
Outer	60×60 mm	720 mm	Fixed to ground.
Mid	50×50 mm	400 mm	First extension stage.
Inner	40×40 mm	300 mm	Second stage, connects to tabletop.

Process for one leg:

Activate component (click on icon in Browser) → Edit In Place.
New Sketch on XZ plane (use component’s own Origin, not the tabletop’s face — learned this the hard way, creates unwanted dependencies).

Centre rectangle → Extrude.
Finish “Edit In Place”.

For concentric alignment: I use Move/Copy (M) with Point to Point mode — selecting centre of smaller tube’s face → centre of larger tube’s face.

moving elements 1/2 — Moving elements 1/2.

moving elements 2/2 — Moving elements 2/2.

Copy to other corners: then I select the three tubes → Ctrl+C → Ctrl+V → Move to position. According to the information in the course mentioned above and a new one, editing one updates all because they’re linked instances ( Magic!! 🥳)

Setting up joints.

1. Ground the outer tubes.

Right-click each Outer_tube → Ground To Parent. This fixes them in space.

2. Create slider joints ( Win Shift+ J).

For each leg, two Slider Joints:

Mid ↔ Outer: Assemble → As-Built Joint → select Mid first, then Outer → Snap on Outer’s top face → Type: Slider.
Inner ↔ Mid: Same process, Inner first, then Mid.

Important: to prevent some weird behaviours, always select the moving component first, fixed component second. Otherwise the wrong part moves.

As-Built Joint dialog with Slider selected.

3. Set Motion Limits.

Right-click each Slider → Edit Motion Limits:

Outer↔Mid: Min 0 mm, Max 320 mm
Mid↔Inner: Min 0 mm, Max 220 mm

Don’t forget to tick both checkboxes or limits won’t apply.

4. Connect tabletop.

As-Built Joint between Tabletop and each Inner_tube → Type: Rigid (no snap needed, just keeps them together).

Animation.

First I tried with Motion Study, but it got weird with linked instances (probably my fault) So, after some digging in Google, I ended up using the Animation Workspace instead.

My process in several steps was: 1. Switch workspace: DESIGN → ANIMATION 2. Timeline appears at bottom. 3. Position playhead at **0s** → components should be at rest position (desk low). 4. Move playhead to **3s** → Select all Mid_tubes → Move (M) up 320 mm. 5. Move playhead to **6s** → Select all Inner_tubes → Move up 220 mm. 6. Hit Play to watch the result.

The tabletop moves automatically because of the Rigid joints with Inner_tubes.

Exporting video.

The basic steps in Fusion, once I was done with my animation, were:

Publish → Video Options.
Resolution: 1920×1080 (there are other options for lighter files, but I wanted to see the size of this one).
Export as AVI.

Compressing with FFmpeg.

As I had no prior experience with this software I checked their site and also asked Claude how to install:

*Show me how to install FFmpeg in Windows 11, using Powershell. Afterwards show me how to compress a video.

As winget wasn’t recognized in my system, I went for option 2:


If winget isn't recognized, use Option 2.

## Option 2 — Manual Installation

### Step 1: Download FFmpeg

1. Go to https://www.gyan.dev/ffmpeg/builds/
2. Download **ffmpeg-release-essentials.zip**
3. Extract to `C:\ffmpeg`

You'll end up with something like:

C:\ffmpeg\ffmpeg-YYYY-MM-DD-git-XXXXXXX-essentials_build\bin\ffmpeg.exe

### Step 2: Add to PATH

Open PowerShell as Administrator and run (adjust the path to match your extracted folder):


[Environment]::SetEnvironmentVariable("Path", $env:Path + ";C:\ffmpeg\ffmpeg-YYYY-MM-DD-git-XXXXXXX-essentials_build\bin", "User")

After closing PowerShell completely, I reopen it, and run the :

ffmpeg -i "input_file.avi" -c:v libx264 -crf 23 -preset medium output.mp4

That line compressed the 10 Mb file exported using Fusion to an insane compression of 146 KB.

Standing desk animation showing telescopic legs extending.

Files.

Find below the files that I made for this assignment.

Adobe Illustrator León’s Fablab logo. Download svg logo.
affinity exploded table. Download svg exploded table file.
Fusion 360 final table assembly. Download FBX model.
Standing desk assembly. Download STL model.

After uploading these files I noticed that the León’s Fab Lab logo wasn’t showing the right font. So, after some digging in the Internet, I found a solution: transform the letters to outlines ( in Illustrator: Type → Create Outlines). Now it shows the original logo and, whoever works with this file in the future will not have to care about having those specific fonts.

Useful links and resources.

Thanks to one of my local instructors, Adrián Torres, I landed in this site from a former Fab Academy student, Mickael Pitarresi. Seeing how he embedded his 3D models using Sketchfab convinced me to do the same. I uploaded my own standing desk assembly and embedded it below (yes, cajeradeldia is me, one of my multiple identities 😁).

standing-desk-assembly by cajeradeldia on Sketchfab

Some inspiration for the standing desk in Sketchfab: